High speed plating of metal with nickel layer - using insoluble anode and controlling nickel ion concn in bath

摘要

A high speed Ni plating process uses an insoluble anode made of e.g. Ni which does not cause a passive state, and the supply of nickel ions into the bath is controlled by the detected pH value of the bath not by the amt. of dissolution of the anode, so as to adjust the pH and Ni ion density in the bath. The supplying Ni ion-contg. contg. soln. is prepared by reacting Ni flakes with a bath in a nickel ion supplying apparatus according to the detected pH value. Plating can be carried out with a high current density of 70 A/dm2 max. without losing the properties of the deposited Ni layer. It is possible to continuously seed the stable Ni plating bath soln. into a bath. When plating Ni on a solder layer, good adhesion can be obtd. between a solder and Ni plated layer without forming a copper strike between the solder layer and Ni plated layer.